Difference between Sleep and Hibernate in Laptops?

Difference between Sleep and Hibernate in Laptops?

-Sleep is a power-saving state that allows a computer to quickly resume full-power operation, Sleep puts your work and settings in memory and draws a small amount of power.

-Hibernation is also a power-saving state designed primarily for laptops. It puts your open documents
 and programs on your hard disk and then turn off your computer.

Off all the power-saving states in Windows, hibernate uses the least amount of power.

If you won't use your laptop for an extended period and won't have an opportunity to charge the battery during that time - Hibernate is most efficient one.